Un-regulation is the biggest selling point and weakness of digital currency. In 2017, ICO financing projects sprang up all over the world. Currency fraud, false advertising, money laundering and others brought by ICO financing projects have attracted the attention of regulators in various countries. Among them, American regulators have incorporated digital currencies into the framework of securities regulation in 2017, and Security Token Offering projects, which are exempted from registration, have gradually emerged since 2018. Securities Token within SEC exemption policy can only be issued to accredited investors and enter the secondary market after the lock-in period. This report will analyze STO's definition, characteristics, business models and successful cases. We find that after the identification of digital coin by SEC, SEC has approved the offerings of several ST projects through Regulation D. Among them, fractions of real estate STOs are more successful, which aims at exploring the way to improve the liquidity of real estate. In addition, STO derives numbers of platforms for the project financers that provide a package of services ranging from technical basis to legal compliance. However, compared with ICO, STO's operation process and sales have not changed qualitatively, and there are still complex structure design and limited equities as well as high opacity. Therefore, investors should maintain a prudent attitude and pay more attention to the underlying assets and product quality to avoid ‘COIN Favor’ and short-term speculation.
